Guitar Pedal Repair

Recently, my band mate Chris‘s guitar pedal has been acting up – when he presses the switch, many times it fails to toggle on and off. Since I happen to have the same pedal, but never use it, I’ve offered to let him borrow mine while I see what I can do to fix his old pedal. I assumed the physical button inside the pedal had worn out, and most likely, others on the web have the same issues.

This pedal happens to be a DigiTech MultiChorus ($80 new), and I assume similar pedals can be repaired the same way.

The pedal has four 7/36″ hex screws in the bottom of the pedal, which are easy to remove and set aside. Inside you will see the bottom of the PCB. To remove this, first take the knobs from the four potentiometers off and loosen the three 1/4″ female jacks from the sides of the case. Carefully pull the board out to reveal the front.

The stomp pad of the pedal makes contact with a small tactile button with a small rubber pad. When power is applied to the board and a 1/4″ cable inserted into the “IN” jack, the button does not toggle the LED light reliably (almost never).

Using a jumper wire, I connected both solder pads on the bottom of the board, which reliably toggles the LED light on and off. The button is the culprit! Easy enough to remove and replace, except that I have no 2 leg tactile buttons – most common ones have 4 legs. After searching for a cheap, US based provider, I found these on Amazon.

To remove the button, I used a soldering iron, a solder sucker and copper desoldering braid to remove the connection to the button and clean up the solder pads on the PCB. After inserting the new button in place, I placed the PCB in a special PCB vice to hold it still, and used silly putty to hold the button in place on the underside of the PCB while I soldered overhead.

Just before soldering, I used a toothpick tip to apply a little flux for further cleaning and allow solder to flow a little easier. With the button soldered in place, I clipped off the remaining button legs, bolted everything back up, and the pedal is back to working like new!